Dear R community, I would like to check differences between treatment (Trait) following a glm. From R help list, I tried in the following way using the multcom library. Please, is it a correct manner to do post hoc comparison with the data below.
Thank you in advance. Sincerely *> tabp<-read.delim("ponteM1.txt")* *> tabp* Trait totponte 1 T 10 2 T 11 3 T 11 4 T 9 5 T 7 6 T 7 7 T 9 8 T 12 9 T 9 10 T 10 11 M 9 12 M 10 13 M 8 14 M 8 15 M 10 16 M 8 17 M 8 18 M 9 19 M 11 20 M 7 21 F 8 22 F 8 23 F 5 24 F 9 25 F 5 26 F 7 27 F 5 28 F 7 29 F 6 30 F 3 *> attach(tabp)* *> glm1<-glm(totponte~Trait,family=poisson)* ** *> anova(glm1,test="F")* Model: poisson, link: log Response: totponte Terms added sequentially (first to last) Df Deviance Resid. Df Resid. Dev F Pr(>F) NULL 29 16.3879 Trait 2 7.1770 27 9.2109 3.5885 0.02764 * * * *> library(multcomp)* *> (coefglm1<-coef(glm1))* (Intercept) TraitM TraitT 1.8405496 0.3342021 0.4107422 *> (vc.trait<-vcov(glm1))* (Intercept) TraitM TraitT (Intercept) 0.01587301 -0.01587301 -0.01587301 TraitM -0.01587301 0.02723665 0.01587301 TraitT -0.01587301 0.01587301 0.02639933 *> (CM<-contrMat(table(tabp$Trait),type="Tukey"))* F M T M-F -1 1 0 T-F -1 0 1 T-M 0 -1 1 * * *> csimint(coefglm1,df=27,covm=vc.trait,cmatrix=CM)* Simultaneous confidence intervals: user-defined contrasts 95 % confidence intervals Estimate 2.5 % 97.5 % M-F -1.506 -2.177 -0.836 T-F -1.430 -2.097 -0.763 T-M 0.077 -0.286 0.439 --------------- Michaël COEURDASSIER, PhD Department of Environmental Biology UsC INRA EA3184MRT Institute for Environmental Sciences and Technology University of Franche-Comte Place Leclerc 25030 Besançon cedex FRANCE Tel : +33 (0)381 665 741 Fax : +33 (0)381 665 797 [EMAIL PROTECTED]: [EMAIL PROTECTED] http://lbe.univ-fcomte.fr/ ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html